JPH0516450A - Data output apparatus - Google Patents

Abstract

PURPOSE:To enhance the use efficiency of the whole of an apparatus by continuously storing residual font data in an auxiliary memory device when all of font data can not be stored in a memory because the quantity of the font data subjected to down load from a host device is much with respect to the capacity of the memory. CONSTITUTION:A laser printer 2 is equipped with a printer controller 4 analyzing printing data such as character data or image data sent from a host computer 1 to convert the same to bit map data in a page unit. In a printer engine 5, laser is modulated corresponding to the bit map data to print a visible image on printing paper. In this case, a readable and writable auxiliary memory device 3 is connected to the printer controller 4 and, when the quantity of font data subjected to down load from a host device is much with respect to the capacity of the memory in the controller 4 and all of font data can not be stored in the memory, residual font data are stored in the auxiliary memory device 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a page printer such as a laser printer, a digital copying machine, a plain paper fax machine, and an information output apparatus such as a CRT display apparatus.

[0002]

2. Description of the Related Art In an information output device such as a laser printer, font data downloaded from a host device (host computer) is expanded into a bitmap format,
It is stored as a font file in the memory in the device.
In such an information output device, when the amount of font data to be downloaded is large and the memory capacity is insufficient, a memory overflow occurs and the font data in the middle of downloading must be deleted and the download must be ended.

Therefore, conventionally, when more font data than the memory capacity is required, when a new memory is added to expand the memory capacity or when font data that has not been downloaded becomes necessary. After deleting other font data in the memory, necessary font data is downloaded, and it is expanded into a bitmap format and stored in an empty area of the memory.

On the other hand, each printer which is an information output device has its own command system, but at present, more printers emulate the command system of other printers in addition to their own command system. I am doing it. In each command system, font data is downloaded by each method, and when the emulation is switched, the downloaded font data used up to that point is cleared in RAM and the newly switched emulation is executed. Is initialized on the RAM.

[0005]

However, in the former information output device, there is a problem that the cost of the entire device increases correspondingly when the memory is expanded. Also, when many downloaded fonts are used with a small memory capacity, if the necessary font data has not been downloaded, it is necessary to suspend the communication of the print data with the host device to download, and the processing time will be reduced. There was a problem of this.

On the other hand, in the latter printer, since the downloaded font in the RAM is erased by switching the emulation, even if the emulation before switching is restored, the font data cannot be used unless it is downloaded again. could not.

The present invention has been made in view of the above points, and solves the above problems and reduces the chances of downloading font data from a host device as much as possible to improve the usage efficiency of the entire device. With the goal.

[0008]

In order to achieve the above object, the present invention downloads font data from a host device and stores it in a memory in the device, and the font data is used to store information such as characters or figures. In the output information output device, if the font data amount to be downloaded from the host device is too large for the readable / writable auxiliary storage device and the above memory capacity and all the font data cannot be stored in the above memory, the remaining fonts Means for continuously storing data in the auxiliary storage device.

Further, in the information output device having means for emulating a plurality of information output devices, the font data downloaded is shared between the means for downloading font data from the host device and the emulated information output device. There is a means for converting, a means for developing a character image on the bitmap memory regardless of the type of the information output device emulated using the font data shared by the means, and the shared font data. And a means for holding the memory area storing the font data even when the emulation is switched, when it is determined that the font data shared by the means exists. Also provided are those with and.

In this information output device, it is preferable to provide a means for selecting whether or not to hold the memory area in which the shared font data is stored when the emulation is switched.

[0011]

According to the first aspect of the invention, when all the font data downloaded from the host device cannot be stored in the memory in the device, the remaining font data is continuously stored in the auxiliary storage device. If the memory does not have the necessary font data, the font data can be downloaded from the auxiliary storage device to avoid the temporary interruption of the communication of the print data with the host device, thus improving the usage efficiency of the device.

According to the second aspect of the invention, the downloaded font data is shared between the emulated information output devices, and the emulated information output device is emulated using the shared font data. It can be expanded on the bitmap memory as a character image regardless of the type. Also, if shared font data exists, the memory area where the font data is stored is retained even if the emulation is switched, so even if the emulation before switching is restored again, that font Data does not have to be downloaded again from the host device.

A means for selecting whether or not to hold the memory area in which the shared font data is stored when the emulation is switched is provided.
If the memory area is not retained when the emulation is switched, the memory in the device can be fully used, and the range of memory usage for the user can be expanded.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be specifically described below with reference to the drawings. FIG. 2 is a system configuration diagram of an embodiment in which the present invention is applied to a laser printer, and 1 is a host computer such as a personal computer, a word processor,
A host computer such as a data processing device and an image processing device, 2 is a laser printer which is a page printer, and 3 is an auxiliary storage device.

The laser printer 2 has character information and images (graphics) sent from the host computer 1.
Bitmap data (video data) is analyzed in page units by analyzing print data such as information or vector information.
A printer controller 4 for converting into a printer, a printer engine 5 including an image forming unit for printing a visible image such as a character or an image on a print sheet by modulating a laser according to the bit map data, a sequence controller for the image forming unit, and the like.
The operation panel 6 includes various indicators and switches.

FIG. 3 is a block diagram showing the internal structure of the printer controller 4. The printer controller 4 has, as an interface (I / F), a host interface 11 for connecting to the host computer 1,
An engine interface 12 for connecting to the printer engine 5, a panel interface 13 for connecting to the operation panel 6, a floppy disk device 14, a readable / writable RAM cartridge 15, and a read-only R.
An auxiliary storage device interface 17 for connecting to the auxiliary storage device 3 such as the OM cartridge 16 is provided.

The printer controller 4 includes a microcomputer (hereinafter referred to as "CPU") 18,
It has a ROM 19 and a RAM 20. The CPU 18 is a general-purpose 16- or 32-bit microcomputer, and controls the printer controller as a whole.
The ROM 19 is a read-on memory and stores resident font data and the like in addition to a program for the CPU 18 to operate.

The RAM 20 is a large capacity random access memory and is mainly used for the following purposes. (a) Input buffer (b) Page buffer (c) Bitmap memory (d) System memory (e) Font file (f) Image file (g) Vector file

For these buffers and files, RAM areas other than those used by the system software are reserved and used in a required capacity in advance. In this case, when the memory capacity is insufficient, the fact is displayed and the function is abandoned. In that case, it is necessary to erase some data and return it to a usable state. That is, instead of fixedly allocating and using the entire memory area, a dynamic management method is used in which an area is secured and used whenever necessary.

The function of each buffer and file will be described below. [Input Buffer] Data is sent from the host computer 1 connected to the host interface 11 irregularly regardless of the operation in the printer controller 4. Therefore, the data from the host interface 11 is temporarily held in the input buffer, and the printer software sequentially extracts and processes the data.

[Page Buffer] Host Computer 1
Add the information such as the source address where the data is actually stored and the destination address and size that specify where in the bitmap memory to create the bitmap data to the data sent from Create page data in the buffer.

[Bitmap Memory] Bitmap data is created in the bitmap memory by using page data of a page buffer and font data of a font file to be described later, or image data of an image file in some cases. This bitmap memory has a full bitmap mode and a partial bitmap mode, and can be used in either mode.

The full bit map mode is a mode in which a memory area corresponding to the entire surface of the paper size is allocated and used as a bit map memory, and the partial bit map mode is a part of the paper size (for example, 1 /
This is a mode in which a memory area corresponding to 8 pages) is allocated as a bitmap memory and half of it is used alternately.

[Font File] All font data is handled as a file, and becomes source data when the bitmap data is expanded in the bitmap memory. Therefore, a list showing addresses that store usable font data and a list showing addresses of characters in each font data are provided in the form of a table.

The font data includes image font data and compressed font data. The image font data is a rectangular dot matrix (bitmap format).
The compressed font data is expressed as a series of data in a 2-digit hexacode. In this embodiment, the font data downloaded from the host computer 1 is developed into a bitmap format and stored in the RAM 20 as a font file.

[Image File] Image data sent from the host computer 1 is sequentially stored to create an image file. When the bitmap memory is in the full bitmap mode, the image data can be directly stored in the bitmap memory without creating this image file. In the partial bitmap mode, it is created in the memory area that can be used as an image file. Then, an identification code is attached to each image file and incorporated in the page buffer.

[Vector File] When the data sent from the host computer 1 is vector information, the vector is created and its address is incorporated in the page buffer. In the case of the partial bit map mode, when the vector information extends over a plurality of page blocks, the file is created by decomposing it in page block units. Even in full bitmap mode,
It is more convenient to decompose the data into small units in terms of memory usage efficiency and processing speed.

Next, the operation of this embodiment thus constructed will be specifically described with reference to FIG. Figure 1
3 is a flowchart showing a process according to the present invention by the CPU 18 of FIG.

This routine starts when font data is downloaded from the host computer 1, and the font data is sequentially expanded into a bitmap format and stored in the RAM (main storage device) 20 as a font foil. Then, if the download is completed before the memory capacity is insufficient, the processing is terminated. However, if the memory capacity is insufficient before the download is completed and a memory overflow is detected, the host computer 1 is caused to interrupt the download. The font data in the middle is deleted.

Next, the memory capacity of the auxiliary storage device 3 is checked, and if there is an empty space, the host computer 1 is caused to start the download again from the beginning of the font data erased during the download, and this is stored in the auxiliary storage device 3
However, if a memory overflow occurs here as well,
Similarly to the above, the font data in the middle of the download is deleted and the download ends.

As described above, according to this embodiment, when all the font data downloaded from the host computer 1 cannot be stored in the RAM 20, the remaining font data is continuously stored in the auxiliary storage device 3, so that R
When the AM 20 does not have the necessary font data, the font data is downloaded from the auxiliary storage device 3 so that the communication of the print data with the host computer 1 is not temporarily interrupted, and the efficiency of use of the device is improved. .

When the memory area of the RAM 20 in which the downloaded font data is stored is needed in the image processing process, the required number of font data are temporarily transferred to the memory of the auxiliary storage device 3. Is also possible.

FIG. 4 is a block diagram of a printer controller showing another embodiment of the present invention. The printer controller 30 includes a host interface 32 for connecting to a host computer 31, an engine interface 34 for connecting to a printer engine 33, and a panel interface 3 for connecting to an operation panel 35.
6, an optional RAM interface 38 for connecting to the optional RAM 37, a ROM cartridge interface 40 for connecting to the ROM cartridge 39
, Each interface circuit, a microcomputer (hereinafter referred to as “CPU”) 41, a ROM 42, a RAM 43, and an EEPROM 44.

The CPU 41 processes the data transmitted from the host computer 31 and performs other control according to the control program stored in the ROM 42 and the data stored in the EEPROM 44. The ROM 42 stores a control program for the printer controller 30, font pattern information for printing, and the like.

The RAM 43 is a work memory used by the CPU 41, an input buffer for temporarily storing data from the host computer 31, and the printer engine 3.
3 is used as a bit map memory for storing bit map data to be output. The EEPROM 44 is a non-volatile memory that stores the contents of the mode set from the operation panel 35.

The option RAM 37 is an RA for temporarily storing bitmap data and download fonts.
This is a RAM for expansion of M51. ROM cartridge 39
Is a font cartridge used when printing is performed using a font other than the font built in the printer controller 30, or an emulation cartridge used when the printer is required to perform another function (emulation of another printer). .

FIG. 5 is an explanatory diagram showing the module configuration of the printer controller 30. The super user consists of a group of modules that control common functions in all emulations, and the emulation consists of a group of modules that controls unique functions of each emulation. The super user has the functions of controlling each interface, handling the input buffer, controlling the drawing (drawing) for the bitmap memory, and jam backup.

The emulation includes handling of a unique font, interpreter of a unique command, and the like. The module that handles download fonts belongs to the emulation part, and the processing format differs depending on the individual emulation.

The download font defined in the command 1 format is sent to the emulation 1,
The interpreter portion of the emulation 1 converts to a common format so that it can be interpreted by the super user. The super user draws in the bitmap memory based on the converted common format, and then outputs a print request to the printer engine 33.

In the emulation 2 as well, the download font defined in the command 2 format is converted into the common format and the same operation is repeated. Also, when there are a plurality of emulations, there is a format for downloading fonts by the number of emulations, but all are converted into a common format in the interpreter part.

The specific command format in emulation 1 when downloading a font is shown below. ESC [m1, m2 @ font-name ESC [header ESC SP ESC SP ESC ^ m11, m12, m13, m14, m15, m16, m17 @ image data 1 ESC ^ m21, m22, m23, m24, m25, m26, m27 @ Image data 2. ． ． ． ． ． ． ． ． ． ． ． ． ． ． ． ． ． ． ． ． ． ． ． ESC ^ mk1, mk2, mk3, mk4, mk5, mk6, mk7 @ image data k ESC]

Here, m1 is a parameter that determines the format in which the image data is arranged. Whether or not this downloaded font is a font for portrait or landscape printing is determined by m2.

The next font header is a set of parameters indicating the attributes of the downloaded font. Among them, the downloaded font is italic, bold, fixed pitch font, proportional font, default H
It includes various font information such as what the MI and VMI values are. FIG. 6 shows an example of the contents of specific attributes of this font header.

Further, mk1 indicates an ASCII code number, and mk2 to mk7 indicate the actual horizontal width of the image, the offset from the left end of the character width to the image (left offset from the cell), and the character width, respectively, as shown in FIG. , The actual vertical height of the image, the offset from the top of the character height to the image (top offset from the cell), and the height of the character.

FIG. 8 shows the contents of the character header of each character, different from the case where the above font header passed the information of the entire font, and each of the above-mentioned mk1 to mk7 indicating the characteristics of each character. Contains information. There are as many character headers as there are characters to download, and immediately after this header the actual image information is sent according to the specified format.

The concrete command format in the emulation 2 when downloading a font is shown below. ESC * c m1 D ESC) s m2 W (font descriptor) ESC * c m3 E ESC (s m4 W (character descriptor & image data)

Here, m1 is the ID number, m2 is the number of bytes of the font header, m3 is the ASCII decimal number, and m4 is the number of bytes of the image & data. This command is different from the command in the emulation 1 described above from the beginning of the escape sequence, and the part corresponding to the font header is called a font descriptor.

As shown in FIG. 9, the font descriptor contains almost the same contents as the font header mentioned above. The character header in the emulation 1 is the character descriptor shown in FIG. 10, and the contents are also very similar. Note that the left offset in FIG. 10 is the offset from the previous print position to the position at which image drawing is started, the top offset is the offset from the top of the image to the baseline, and Delta X is the next print from the previous print position. The length to each position (dot) is shown.

Generally, as shown in FIG. 11, first, an escape sequence is sent, then a font header containing common information of fonts is sent, and then character header information and image data for each code are sent by the number of codes. The font information is converted into a format common to each emulation in the emulation 1 and the emulation 2 so that it can be interpreted by the super user.

In this embodiment, a plurality of emulations exist by storing this common format in a specific area and controlling the memory not to be cleared only for this specific area even if the emulation is changed. Even if the emulation is switched in the printer, the downloaded font can be used in common.

FIGS. 12, 13 and 14 show specific examples of common formats converted by emulation of the file header, font header and character header, respectively. In FIG. 14, dw is the width of the image in the main scanning direction, dh is the width of the image in the sub-scanning direction, iw is the width of the image, ih is the height of the image, cw is the width of the cell,
dx represents the amount of movement of the active position.

FIG. 15 shows the input buffer, variable area, bitmap area and download font storage area in the RAM 43. The common format is stored in the download font storage area.

FIG. 16 is a flow chart showing the processing according to the present invention by the CPU 41 in this embodiment. First, it is judged whether or not an instruction to change the emulation is given. If the instruction to change the emulation is given, the shared download is made. It is determined whether or not the font (common format) exists in the RAM 43.

If the shared download font does not exist in the RAM 43, all areas (data) in the RAM 43 are cleared, and then the emulation is switched so that the shared download font exists. In this case, after clearing the area other than the download font storage area in RAM43,
Switch emulation.

As described above, according to this embodiment, the downloaded font data is shared between the emulated printers, and the memory area in which the shared font data is stored is switched for emulation. Even if the emulation before switching is restored, the font data does not have to be downloaded again from the host computer 31 because it is retained.

FIG. 17 is a flow chart showing the processing by the CPU 41 different from that of FIG. 16 according to the present invention.
First, it is determined whether or not an instruction to change the emulation is given. When the instruction to change the emulation is given, an operation signal from the operation panel 35 or the host computer 31 is sent.
It is determined whether or not the download font common use mode (mode in which the download font storage area in the RAM 43 is not cleared) is set by the command from.

If the download font common use mode is not set, the emulation is switched after clearing all areas in the RAM 43, and if the download font common use mode is set, It is judged whether or not the shared download font exists in the RAM 43, and even if it does not exist, all the areas in the RAM 43 are cleared, and then the emulation is switched.

If there is a shared download font, the area other than the download font storage area in the RAM 43 is cleared and then the emulation is switched.

According to this processing, when the user does not select the download font common use mode, the RAM 43
Although the download font storage area in is also cleared, by doing so, the RAM 43 can be fully used and the range of use of the memory for the user can be expanded.

The embodiments in which the present invention is applied to a laser printer have been described above, but the present invention is not limited to this, and other page printers such as LED printers, as well as various types such as digital copying machines and plain paper fax machines. The present invention is applicable to image forming apparatuses and various information processing apparatuses such as CRT display devices.

[0061]

As described above, according to the present invention, the chances of downloading font data from the host device are significantly reduced, and the efficiency of use of the entire device is improved.

[Brief description of drawings]

FIG. 1 is a flowchart showing a process according to the present invention by a CPU 18 of FIG.

FIG. 2 is a system configuration diagram of an embodiment in which the present invention is applied to a laser printer.

3 is a block diagram showing an internal configuration of the printer controller of FIG.

FIG. 4 is a block diagram showing an internal configuration of a printer controller according to another embodiment of the present invention.

5 is an explanatory diagram showing a module configuration of the printer controller of FIG.

6 is an explanatory diagram showing an example of a font header corresponding to the emulation 1 of FIG.

FIG. 7 is an explanatory diagram for explaining a command for downloading a font corresponding to emulation 1 in the same manner.

FIG. 8 is an explanatory diagram showing an example of a character header of individual characters corresponding to emulation 1 as well.

FIG. 9 is an explanatory diagram showing an example of a font descriptor corresponding to the emulation 2 as well.

10 is an explanatory diagram showing an example of a character descriptor of an individual character corresponding to the emulation 2 as well. FIG.

FIG. 11 is an explanatory diagram showing a general command format for downloading a font.

12 is an explanatory diagram showing an example of a common format of a file header converted by each emulation of FIG.

FIG. 13 is an explanatory diagram showing an example of a common format of font headers converted by each emulation.

FIG. 14 is an explanatory diagram showing an example of a common format of the character header converted by each emulation.

15 is a memory map diagram showing a memory area in a RAM 43 of FIG.

16 is a flowchart showing a process according to the present invention by the CPU 41 of FIG.

FIG. 17 is a flowchart showing the processing by the CPU 41 of FIG. 4 different from that of FIG. 16 according to the present invention.

[Explanation of symbols]

1, 31 Host Computer 2 Laser Printer 3 Auxiliary Storage Device 4, 30 Printer Controller 5, 33 Printer Engine 6, 35 Operation Panel 14 Floppy Disk 15 RAM Cartridge 18, 41 CPU 19, 42 ROM 20, 43 RAM 44 EEPROM

Claims (3)

[Claims] 1. An information output device for downloading font data from a host device, storing the font data in a memory in the device, and outputting information such as characters or graphics using the font data, a readable / writable auxiliary storage device, When the amount of font data downloaded from the host device is large relative to the capacity of the memory and all the font data cannot be stored in the memory, the remaining font data is continuously stored in the auxiliary storage device. An information output device comprising: 2. An information output device having means for emulating a plurality of information output devices, wherein the downloaded font data is shared between a means for downloading font data from a host device and the emulated information output device. There is a means for converting, a means for developing a character image on the bitmap memory regardless of the type of the information output device emulated using the font data shared by the means, and the shared font data. And a means for holding the memory area storing the font data even when the emulation is switched, when it is determined that the font data shared by the means exists. An information output device comprising: 3. The information output device according to claim 2,
An information output device comprising means for selecting whether to hold a memory area storing shared font data when emulation is switched.